对投入与产出优化分析方法的应用探讨

介绍投入与产出优化分析的一些基本概念和计算方法 ,并结合实际 ,举例说明投入与产出的优化分析方法具体应用     

数据包络分析方法在朝阳市农业干旱用水效率的测算应用

文章采用数据包络分析方法,对朝阳市农业干旱用水效率进行测算。测算结果表明:当朝市农业产出和投入指标分别为0.45和0.56时,农业干旱用水效率一般50%,应加强农业产出和投入指标的优化,从而提高农业干旱用水效率。     

灌区投入占用产出模型

根据灌区特点建立了灌区投入占用产出模型，结合韶山灌区情况编制了灌区投入占用产出表，根据此表可对灌区进行经济分析研究. 利用该模型揭示了灌区水资源对区域经济增长所产生的直接和间接的影响， 及灌区经济发展的内部联系. 该投入占用产出模型可以在一定范围内、一定程度上、一定时间内模拟该地区经济生产各部门、各企业实际生产的物质及价值联系和平衡关系，从整个经济系统上去把握总体经济发展的规律性，安排投入、产出任务，以创造更多的最终产品. 本文的灌区投入占用产出模型可移用于其他地区。     

水电工程施工安全投入与产出效益研究

目前我国水电工程施工存在着安全投入管理不足、安全投入与安全产出不平衡的问题。本文通过对水利水电工程施工进行分析,得到安全投入与产出的内容和量化公式,通过安全投入与产出效益的关系,引入工程安全的投入消耗、效益、事故损失等系数指标,构建水电施工安全效益模型,将模型运用到实际工程管理中,使产出效益与安全投入达到最佳效果。对实际工程案例进行数据分析,使安全投入与安全产出得到合理的分配,计算出水利水电工程施工的安全评价指标系数,为今后的水电工程施工提供数据模型支持,以有助于工程的安全投入与管理。     

论增加防洪工程投入的必要性和紧迫性

本文从安徽的历史洪灾和建国后共工程的投入与产出，以及当前防洪工程存在的问题，阐述增加防洪工程投入的必要性和紧迫性，并提出增加投入的几点建议。     

水库移民土地调配中政府协调路径构建

土地是农民赖以生存的条件，土地调配是水库移民安置中的关键问题。为实现库区社会、经济及环境的可持续发展，需充分发挥政府在土地调配中的协调作用。通过实地调查及移民安置实践等方式，从风险管理角度出发，采用公平理论，建立土地调配参照物标准和移民投入与产出心理预期所涉及的因素组成的指标体系，对移民的投入、产出预期进行分析。综合考虑政府组织灵活度与移民投入、产出的预期，设计出水库移民土地调配中政府协调路径。该思路可提前预防问题及矛盾的产生。     

投入占用产出技术及其在经济分析和研究中的应用

本文分三部分,第一部分介绍美国科学家W.Leontief所首创的投入产出分析,第二部分介绍我国学者所提出的投入占用产出技术,最后部分综合地介绍了投入占用产出技术在我国经济分析和研究中的应用,以及在水利方面的应用。     

江苏省水资源宏观经济模型研究

1 问题的提出。投入产出法是研究经济系统各部分投入与产出间相互依存关系的一种数量分析方法。投入产出表是投入产出法的核心，它反映了国民经济中各部门的投入来源与产出去向，其重要功能就是为投入产出分析提供系统的统计数据。根据投入产出表的经济内容和平衡关系，建立线性方程组．该方程组就是投入产出的数学模型。     

数据包络分析在灌溉效益评价中的应用

本文分析了评价灌溉效益的众多指标,其中包括很多不能量化的非经济指标,基于投入—产出的思想将评价灌溉效益的诸指标分为投入指标和产出指标两大类,对灌溉效益进行综合评价,最后利用数据包络分析模型的二阶段法进行求解,并将其运用到实际中。     

我国水利投资状况与国民经济关系分析

从水利投入政策和水利投资流向2个方面分析了1949年以来水利的投资状况;采用弹性系数、影响力系数、感应度系数等定量指标对水利投资与国民经济发展之间的关系进行分析,认为水利投入应优先于其他行业投入,其增长只有高于国民经济产出的增长才能优化资源配置,协调国民经济的发展。     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.